Process of coating one metal with another



salient HEMAN TnUns'ron, or none cannon, Nnnfsnnsnvil rRocEss or commaearners. was ANOTHER, ac.

srncrrrcn'rron' fog of, Letters Patent no. scares, dated n rn 11,1eea.

'llpplicatlon filed July 2, 1898- fierlal No. 685.073, e spec m s- Toall whom it may concern: lie itlrnovvn that l, SAMUEL Harms THURS- rot acitizen of the United States of America. residing at Long Branchponntyof Monmouth, E 5 State of New Jersey, have invented and made a certainnew process for coating one metal with another, such as ironand steelwith cop- .4 per, and a new product as the result of such process; and Ido hereby declare that the folto lowing is a full, clear, and exactdescription and specification oi the same.

My invention relates to the coating of metals in general with anothermetal of a softer nature in order to protect it from oxidation,

r 5 and, specifically, to coating" iron and steel with copper hint orpelnicle, and to the furnishing of a product having" a surface coatingpractically permanent in its nature in regard to its appearance andpower of resisting changes from contact with the atmosphere; and itconsists in a certain method of procedure fully set forth in thisspecification and claimed at the end thereof. a I in order that personsskilled in the art to which my invention appertains may understand,perform, and use my inventiornl will proceed to describe it. is

i am aware that it is old in the art to coat one metal with another forvarious purposes by electrical'process, by dipping in molten metal, bydipping in hot solution, by rolling two metals together after solderingthem, and by rnhhing an alloy of metal on iron to give color; but I amnot aware that one metal has ever before my invention been permanentlysecured to another metal by rneans of the proc css I am about todescrihemorhas any pl ednct ever been known in any way similar to theproduct which is furnished by the practice of an my invention or processor ever produced by any other means,whether by my process or not. Myinvention is confined to coating iron and its derivativesvvith a film ofcopper oxidil shall in this present specification partieslarly-sodescribe the steps necessary for this] purpose. V-

Having thoroughly cleaned thesnrfaces of the iron tolbecoatcdby'cleaning I mean purifying the surfaces from matter whichprevents cohhsionof the coating metal with the molecules of the iron--Irub the said surfaces with copper until a thin coherent film f and tocoherevvith then].

film to a heat sufficient to turn the said film to a deepblne-hlack,-and leave on the iron a thin skin of hlack oxid of copper orcupric .oxid, which adheres so tenaciously to the iron ;as topractically'forin a part of the iron itself. ll sometimes heat the ironbefore coating it may be applied in the manner heretofore deadherestothe iron, This may best he done by light frictional impact oftrepented, as

with revolving copper hrnshes, which causes 55 the copper to impinge orbeimpacted against the iron molecules and into the interstices X I thenpreferably heatthe iron provided with thesaid copper 6 Q to drive edany'inoistnre there rnighthe present. .The cnpric oxid formed is verydense; and quite black and serves as a perfect protection for the ironagainst the atmospheric attacks. It is to he here stated that the copper'filni- "will adhere to the iron and protect its surfaces, even if it isnot changed to a] black cnpricoxid, and for some especial purposes Ipropose to stop myprocess at this point. This copper filin adheres sotenaciously to the iron as to resist removal by bending, rolling, orhammering, and can only he filed oft orremovedhy'abrasion- Coat aftercoat scribed nntila thickness is attained suitable for the uses toWhichthe product is to be put. This is particularly true when the cnpricoxid is formed from the film, and a copper film may he formed over thecupric-oxid filrn'and not again heated to form another coating of cupricoxid; but I prefer for most purposes to carrytmy process to its fulllimit and leave a film of cupric black anhydrous oxid of copper on theiron of such thickness as will he .suflicient'for the special purposesneeded.

. lam aware of the United States patents to Bower, January 2, 1883, andSpring, N ovemher 27, 1877; of English patents to Dowling', 1839,

.,No.'7,949, and to Barron, May 24,1855, No. 1,243, and I do not claimanything set out in said patents. By exhaustive experiments I havedetermined that the oxids of copperwill not stick to copper, astheircoemcient of expansion is difierent from the coeflicient of expansion ofcopper, while the coeficient of expansion of copperoxid" and that ofiron cor-. respond closely-enough to prevent scaling oil. I have appliedcopperih a comminutedform;

'but I prefer to comminnte it by rubbing it on 5 what I claim as new andas my invention, and

desire to secure by Letters Patent, is-

"' '1. The within-described process of coating 'iron and steel withcopper oxid, which con- Y sists in first oleaningthe iron to be coatedand IO then causing either metal to impinge upon the other metal until afilm of copper is impncted upon the iron to be coated, and then heatingthe said film to the desired tempereture to form cupric oxid,snbstantiallyas end for the purposes hereinbefore specified.

2. The within-described product consisting of iron or steel covered withan adherentcoating of oxid of copper, substantially such as hereinbeforespecified.

SAMUEL HEMAN 'rnunsrom Witnesses:

.Lmns M. HICKS, .CnARLEs W. Low.

